I do agree with useful comments in code though I'm sure I don't do it as much as I should (New Year's resolution time). However my personal pet hate is commented out code. These days I general use a pretty editor with syntax highlighting, so it's a lot easier to ignore all the 'green stuff'. In the days of black and white editors (and some people still LIKE vi), it is very easy to lose track of what is 'real' code and what was code three years ago but isn't anymore. [I've read that some 'spawn of vi' editors do have syntax highlighting, but all I get is plain vanilla vi.]
IMHO (and that's all this blog is) dead code belongs in source control history and no place else. If you absolutely MUST comment out code, use the -- form of comments so that people don't have to page up and down to work out whether the code they are looking at is still being used or not.